Java/Regular Expressions/Lookup
Содержание
Java Regular Expression : File and Find
<source lang="java">
/* From http://java.sun.ru/docs/books/tutorial/index.html */ /*
* Copyright (c) 2006 Sun Microsystems, Inc. All Rights Reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * -Redistribution of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * -Redistribution in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * Neither the name of Sun Microsystems, Inc. or the names of contributors may * be used to endorse or promote products derived from this software without * specific prior written permission. * * This software is provided "AS IS," without a warranty of any kind. ALL * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE * OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN") * AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE * AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, * INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY * OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE, * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. * * You acknowledge that this software is not designed, licensed or intended * for use in the design, construction, operation or maintenance of any * nuclear facility. */
import java.io.BufferedReader; import java.io.FileNotFoundException; import java.io.FileReader; import java.io.IOException; import java.util.regex.Matcher; import java.util.regex.Pattern; public final class RegexTestHarness {
private static String REGEX; private static String INPUT; private static BufferedReader br; private static Pattern pattern; private static Matcher matcher; private static boolean found; public static void main(String[] argv) { initResources(); processTest(); closeResources(); } private static void initResources() { try { br = new BufferedReader(new FileReader("regex.txt")); } catch (FileNotFoundException fnfe) { System.out .println("Cannot locate input file! " + fnfe.getMessage()); System.exit(0); } try { REGEX = br.readLine(); INPUT = br.readLine(); } catch (IOException ioe) { } pattern = Pattern.rupile(REGEX); matcher = pattern.matcher(INPUT); System.out.println("Current REGEX is: " + REGEX); System.out.println("Current INPUT is: " + INPUT); } private static void processTest() { while (matcher.find()) { System.out.println("I found the text \"" + matcher.group() + "\" starting at index " + matcher.start() + " and ending at index " + matcher.end() + "."); found = true; } if (!found) { System.out.println("No match found."); } } private static void closeResources() { try { br.close(); } catch (IOException ioe) { } }
}
</source>
Java Regular Expression : find 2
<source lang="java">
/* From http://java.sun.ru/docs/books/tutorial/index.html */ /*
* Copyright (c) 2006 Sun Microsystems, Inc. All Rights Reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * -Redistribution of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * -Redistribution in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * Neither the name of Sun Microsystems, Inc. or the names of contributors may * be used to endorse or promote products derived from this software without * specific prior written permission. * * This software is provided "AS IS," without a warranty of any kind. ALL * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE * OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN") * AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE * AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, * INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY * OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE, * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. * * You acknowledge that this software is not designed, licensed or intended * for use in the design, construction, operation or maintenance of any * nuclear facility. */
import java.io.BufferedReader; import java.io.FileNotFoundException; import java.io.FileReader; import java.io.IOException; import java.util.regex.Matcher; import java.util.regex.Pattern; import java.util.regex.PatternSyntaxException; public final class RegexTestHarness2 {
private static String REGEX; private static String INPUT; private static BufferedReader br; private static Pattern pattern; private static Matcher matcher; private static boolean found; public static void main(String[] argv) { initResources(); processTest(); closeResources(); } private static void initResources() { try { br = new BufferedReader(new FileReader("regex.txt")); } catch (FileNotFoundException fnfe) { System.out .println("Cannot locate input file! " + fnfe.getMessage()); System.exit(0); } try { REGEX = br.readLine(); INPUT = br.readLine(); } catch (IOException ioe) { } try { pattern = Pattern.rupile(REGEX); matcher = pattern.matcher(INPUT); } catch (PatternSyntaxException pse) { System.out .println("There is a problem with the regular expression!"); System.out.println("The pattern in question is: " + pse.getPattern()); System.out.println("The description is: " + pse.getDescription()); System.out.println("The message is: " + pse.getMessage()); System.out.println("The index is: " + pse.getIndex()); System.exit(0); } System.out.println("Current REGEX is: " + REGEX); System.out.println("Current INPUT is: " + INPUT); } private static void processTest() { while (matcher.find()) { System.out.println("I found the text \"" + matcher.group() + "\" starting at index " + matcher.start() + " and ending at index " + matcher.end() + "."); found = true; } if (!found) { System.out.println("No match found."); } } private static void closeResources() { try { br.close(); } catch (IOException ioe) { } }
}
</source>
Negative Look ahead
<source lang="java">
import java.util.regex.Matcher; import java.util.regex.Pattern; public class NegativeLookaheadExample {
public static void main(String args[]) throws Exception { String regex = "John (?!Smith)[A-Z]\\w+"; Pattern pattern = Pattern.rupile(regex); String candidate = "I think that John Smith "; candidate += "is a fictional character. His real name "; candidate += "might be John Jackson, John Westling, "; candidate += "or John Holmes for all we know."; Matcher matcher = pattern.matcher(candidate); String tmp = null; while (matcher.find()) { tmp = matcher.group(); System.out.println("MATCH:" + tmp); } }
}
</source>
Positive Look ahead
<source lang="java">
import java.util.regex.Matcher; import java.util.regex.Pattern; public class PositiveLookaheadExample {
public static void main(String args[]) { String regex = "(?=^255).*"; Pattern pattern = Pattern.rupile(regex); String candidate = "255.0.0.1"; Matcher matcher = pattern.matcher(candidate); String ip = "not found"; if (matcher.find()) ip = matcher.group(); String msg = "ip: " + ip; System.out.println(msg); }
}
</source>
Positive Look behind 1
<source lang="java">
import java.util.regex.Matcher; import java.util.regex.Pattern; public class PositiveLookBehindExample {
public static void main(String args[]) throws Exception { String regex = "(?<=http://)\\S+"; Pattern pattern = Pattern.rupile(regex); String candidate = "The jexp website can be found at "; candidate += "http://www.jexp.ru. There, "; candidate += "you can find some Java examples."; Matcher matcher = pattern.matcher(candidate); while (matcher.find()) { String msg = ":" + matcher.group() + ":"; System.out.println(msg); } }
}
</source>
Positive Look Behind 2
<source lang="java">
import java.util.regex.Matcher; import java.util.regex.Pattern; public class PositiveLookBehindExample {
public static void main(String args[]) throws Exception { String regex = "(?<=http://)\\S+"; Pattern pattern = Pattern.rupile(regex); String candidate = "The jexp website can be found at "; candidate += "http://www.jexp.ru. There, "; candidate += "you can find some best example code for Java."; Matcher matcher = pattern.matcher(candidate); while (matcher.find()) { String msg = ":" + matcher.group() + ":"; System.out.println(msg); } }
}
</source>
Positive Look Behind 3
<source lang="java">
import java.util.regex.Matcher; import java.util.regex.Pattern; public class PositiveLookBehindExample {
public static void main(String args[]) throws Exception { String regex = "(?<=http://)\\S+"; Pattern pattern = Pattern.rupile(regex); String candidate = "The jexp website can be found at "; candidate += "http://www.jexp.ru. There, "; candidate += "you can find information about some of "; candidate += "best example codes"; Matcher matcher = pattern.matcher(candidate); while (matcher.find()) { String msg = ":" + matcher.group() + ":"; System.out.println(msg); } }
}
</source>
Regular Expression: find
<source lang="java">
/* From http://java.sun.ru/docs/books/tutorial/index.html */ /*
* Copyright (c) 2006 Sun Microsystems, Inc. All Rights Reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * -Redistribution of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * -Redistribution in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * Neither the name of Sun Microsystems, Inc. or the names of contributors may * be used to endorse or promote products derived from this software without * specific prior written permission. * * This software is provided "AS IS," without a warranty of any kind. ALL * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE * OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN") * AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE * AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, * INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY * OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE, * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. * * You acknowledge that this software is not designed, licensed or intended * for use in the design, construction, operation or maintenance of any * nuclear facility. */
import java.util.regex.Matcher; import java.util.regex.Pattern; public final class MatcherTest {
private static final String REGEX = "\\bdog\\b"; private static final String INPUT = "dog dog dog doggie dogg"; public static void main(String[] argv) { Pattern p = Pattern.rupile(REGEX); Matcher m = p.matcher(INPUT); // get a matcher object int count = 0; while (m.find()) { count++; System.out.println("Match number " + count); System.out.println("start(): " + m.start()); System.out.println("end(): " + m.end()); } }
}
</source>